Application of biogas slurries from energy crops to arable soils and their impact on carbon and nitrogen dynamics

The use of renewable primary products as co-substrate or single substrate for biogas production has increased consistently over the last few years. Maize silage is the preferential energy crop used for fermentation due to its high methane (CH4) yield per hectare. Equally, the by-product, namely biogas slurry (BS), is used with increasing frequency as organic fertilizer to return nutrients to the soil and to maintain or increase the organic matter stocks and soil fertility. Studies concerning the application of energy crop-derived BS on the carbon (C) and nitrogen (N) mineralization dynamics are scarce. Thus, this thesis focused on the following objectives: I) The determination of the effects caused by rainfall patterns on the C and N dynamics from two contrasting organic fertilizers, namely BS from maize silage and composted cattle manure (CM), by monitoring emissions of nitrous oxide (N2O), carbon dioxide (CO2) and CH4 as well as leaching losses of C and N. II) The investigation of the impact of differences in soil moisture content after the application of BS and temperature on gaseous emissions (CO2, N2O and CH4) and leaching of C and N compounds. III) A comparison of BS properties obtained from biogas plants with different substrate inputs and operating parameters and their effect on C and N dynamics after application to differently textured soils with varying application rates and water contents. For the objectives I) and II) two experiments (experiment I and II) using undisturbed soil cores of a Haplic Luvisol were carried out. Objective III) was studied on a third experiment (experiment III) with disturbed soil samples. During experiment I three rainfall patterns were implemented including constant irrigation, continuous irrigation with periodic heavy rainfall events, and partial drying with rewetting periods. Biogas slurry and CM were applied at a rate of 100 kg N ha-1. During experiment II constant irrigation and an irrigation pattern with partial drying with rewetting periods were carried out at 13.5°C and 23.5°C. The application of BS took place either directly before a rewetting period or one week after the rewetting period stopped. Experiment III included two soils of different texture which were mixed with ten BS’s originating from ten different biogas plants. Treatments included low, medium and high BS-N application rates and water contents ranging from 50% to 100% of water holding capacity (WHC). Experiment I and II showed that after the application of BS cumulative N2O emissions were 4 times (162 mg N2O-N m-2) higher compared to the application of CM caused by a higher content of mineral N (Nmin) in the form of ammonium (NH4+) in the BS. The cumulative emissions of CO2, however, were on the same level for both fertilizers indicating similar amounts of readily available C after composting and fermentation of organic material. Leaching losses occurred predominantly in the mineral form of nitrate (NO3-) and were higher in BS amended soils (9 mg NO3--N m-2) compared to CM amended soils (5 mg NO3--N m-2). The rainfall pattern in experiment I and II merely affected the temporal production of C and N emissions resulting in reduced CO2 and enhanced N2O emissions during stronger irrigation events, but showed no effect on the cumulative emissions. Overall, a significant increase of CH4 consumption under inconstant irrigation was found. The time of fertilization had no effect on the overall C and N dynamics. Increasing temperature from 13.5°C to 23.5°C enhanced the CO2 and N2O emissions by a factor of 1.7 and 3.7, respectively. Due to the increased microbial activity with increasing temperature soil respiration was enhanced. This led to decreasing oxygen (O2) contents which in turn promoted denitrification in soil due to the extension of anaerobic microsites. Leaching losses of NO3- were also significantly affected by increasing temperature whereas the consumption of CH4 was not affected. The third experiment showed that the input materials of biogas plants affected the properties of the resulting BS. In particular the contents of DM and NH4+ were determined by the amount of added plant biomass and excrement-based biomass, respectively. Correlations between BS properties and CO2 or N2O emissions were not detected. Solely the ammonia (NH3) emissions showed a positive correlation with NH4+ content in BS as well as a negative correlation with the total C (Ct) content. The BS-N application rates affected the relative CO2 emissions (% of C supplied with BS) when applied to silty soil as well as the relative N2O emissions (% of N supplied with BS) when applied to sandy soil. The impacts on the C and N dynamics induced by BS application were exceeded by the differences induced by soil texture. Presumably, due to the higher clay content in silty soils, organic matter was stabilized by organo-mineral interactions and NH4+ was adsorbed at the cation exchange sites. Different water contents induced highest CO2 emissions and therefore optimal conditions for microbial activity at 75% of WHC in both soils. Cumulative nitrification was also highest at 75% and 50% of WHC whereas the relative N2O emissions increased with water content and showed higher N2O losses in sandy soils. In summary it can be stated that the findings of the present thesis confirmed the high fertilizer value of BS’s, caused by high concentrations of NH4+ and labile organic compounds such as readily available carbon. These attributes of BS’s are to a great extent independent of the input materials of biogas plants. However, considerably gaseous and leaching losses of N may occur especially at high moisture contents. The emissions of N2O after field application corresponded with those of animal slurries.

The trees and the bees: using enforcement and income projects to protect forests and rural livelihoods through spatial joint production

Forest managers in developing countries enforce extraction restrictions to limit forest degradation. In response, villagers may displace some of their extraction to other forests, which generates “leakage” of degradation. Managers also implement poverty alleviation projects to compensate for lost resource access or to induce conservation. We develop a model of spatial joint production of bees and fuelwood that is based on forest-compatible projects such as beekeeping in Thailand, Tanzania, and Mexico. We demonstrate that managers can better determine the amount and pattern of degradation by choosing the location of both enforcement and the forest-based activity.

Advanced feature selection methods in multinominal dementia classification from structural MRI data

Recent studies showed that features extracted from brain MRIs can well discriminate Alzheimer’s disease from Mild Cognitive Impairment. This study provides an algorithm that sequentially applies advanced feature selection methods for findings the best subset of features in terms of binary classification accuracy. The classifiers that provided the highest accuracies, have been then used for solving a multi-class problem by the one-versus-one strategy. Although several approaches based on Regions of Interest (ROIs) extraction exist, the prediction power of features has not yet investigated by comparing filter and wrapper techniques. The findings of this work suggest that (i) the IntraCranial Volume (ICV) normalization can lead to overfitting and worst the accuracy prediction of test set and (ii) the combined use of a Random Forest-based filter with a Support Vector Machines-based wrapper, improves accuracy of binary classification.

Computer techniques towards the automatic characterization of graphite particles in metallographic images of industrial materials

The automatic characterization of particles in metallographic images has been paramount, mainly because of the importance of quantifying such microstructures in order to assess the mechanical properties of materials common used in industry. This automated characterization may avoid problems related with fatigue and possible measurement errors. In this paper, computer techniques are used and assessed towards the accomplishment of this crucial industrial goal in an efficient and robust manner. Hence, the use of the most actively pursued machine learning classification techniques. In particularity, Support Vector Machine, Bayesian and Optimum-Path Forest based classifiers, and also the Otsu's method, which is commonly used in computer imaging to binarize automatically simply images and used here to demonstrated the need for more complex methods, are evaluated in the characterization of graphite particles in metallographic images. The statistical based analysis performed confirmed that these computer techniques are efficient solutions to accomplish the aimed characterization. Additionally, the Optimum-Path Forest based classifier demonstrated an overall superior performance, both in terms of accuracy and speed. © 2012 Elsevier Ltd. All rights reserved.

Avaliação do potencial invasivo de espécies não-nativas utilizadas em plantio de restauração de matas ciliares

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Certificação florestal: uma análise dos protocolos do FSC para emissão de selo verde e das normas estatais para licenciamento florestal no estado do Pará

A pesquisa teve como objetivo Identificar se as normas estatais para licenciamento florestal no Estado do Pará interferem positiva ou negativamente na adoção da certificação de manejo florestal do sistema do conselho de manejo florestal (FSC). A abordagem metodológica foi à qualitativa, com o uso da estatística descritiva para apoiar interpretações e/ou conclusões firmadas a respeito da análise dos dados coletados. A população amostral foi composta pelos empreendimentos de manejo florestal (EMF) do Estado do Pará, com certificado do FSC. Os dados e informações foram coletados em relatórios e documentos do FSC, Instituto Brasileiro de Meio Ambiente e Recursos Naturais Renováveis (IBAMA), Secretaria de Estado de Meio Ambiente do Pará (SEMA) e Instituto do Homem e Meio Ambiente da Amazônia (IMAZON). O resultado da pesquisa demonstrou que as normas estatais para licenciamento florestal no Estado do Pará interferem negativamente na certificação florestal, pois a análise das auditorias realizadas nos EMF, com certificado florestal no Estado do Para, demonstraram que mesmo, os EMF que possuem a certificação há mais de cinco anos, ainda apresentam não conformidades relacionadas ao não cumprimento da legislação ambiental e as estatísticas sobre a produção madeireira na Amazônia apontam que as normas estatais para licenciamento florestal ainda não são efetivas no combate a produção de madeira ilegal no Estado Pará, o que provoca uma concorrência desleal para o mercado de produtos de base florestal certificados.

Obtenção dos parâmetros e estudo cinético da hidrólise ácida dos resíduos florestais de eucalipto

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The long-term effects of whole-tree harvest at final felling on soil properties in a Norway Spruce (Picea Abies (L) Karst.) Stand

Increased demand for forest-derived biomass has resulted in changes in harvest intensities in Finland. Conventional stem-only harvest (CH) has to some extent been replaced with whole-tree harvest (WTH). The latter involves a greater removal of nutrients from the forest ecosystem, as all the above ground biomass is exported from the site. This has raised concerns that WTH could result in large changes in the nutrient dynamics of a forest stand and could eventually lower its site productivity. Little empirical data exists to support this assumption as only a limited number of studies have been conducted on the topic. A majority of these discuss the short-term effects, thus the long-term consequences remain unknown. The objective of this study was to compare differences in soil properties after CH and WTH in a fertile Norway spruce (Picea abies (L) Karst.) stand in Southern Finland. The site was clear-felled in August 2000 and spruce seedlings were planted in the following summer. Soil sampling in the form of systematic randomized sampling was carried out in May 2011. Changes in base saturation, cation exchange capacity, elemental pools (total and exchangeable) and acidity were studied in both organic and mineral horizons. The results indicate that WTH lowered effective cation exchange capacity and base saturation particularly in the humus layer. The pools of exchangeable Al and Fe were increased in the humus layer, whereas the amount of exchangeable Ca decreased in both layers. WTH also resulted in lower Ca/Al-ratios across the sampled layers. Treatment did not have a significant effect on pH, total pools of elements or on the C/N-ratio of the soil. The results suggest that although the stand possesses significant pools of nutrients at present, WTH, if continued, could have long-term effects on site productivity.

Institutions for sustainable governance of forests: Equity, robustness and cross-level interactions in Mawlyngbna, Meghalaya, India

This study adopts Ostrom’s Social-Ecological Systems (SES) framework in empirical fieldwork to explain how local forestry institutions affect forest ecosystems and social equity in the community of Mawlyngbna in North-East India. Data was collected through 26 semi-structured interviews, participatory timeline development, policy documents, direct observation, periodicals, transect walks, and a concurrent forest-ecological study in the village. Results show that Mawlyngbna's forests provide important sources of livelihood benefits for the villagers. However, ecological disturbance and diversity varies among the different forest ownership types and forest-based livelihood benefits are inequitably distributed. Based on a bounded rationality approach, our analysis proposes a set of causal mechanisms that trace these observed social-ecological outcomes to the attributes of the resource system, resource units, actors and governance system. We analyse opportunities and constraints of interactions between the village, regional, and state levels. We discuss how Ostrom’s design principles for community-based resource governance inform the explanation of robustness but have a blind spot in explaining social equity. We report experiences made using the SES framework in empirical fieldwork. We conclude that mapping cross-level interactions in the SES framework needs conceptual refinement and that explaining social equity of forest governance needs theoretical advances.

Automatic quality control in clinical (1) H MRSI of brain cancer.

MRSI grids frequently show spectra with poor quality, mainly because of the high sensitivity of MRS to field inhomogeneities. These poor quality spectra are prone to quantification and/or interpretation errors that can have a significant impact on the clinical use of spectroscopic data. Therefore, quality control of the spectra should always precede their clinical use. When performed manually, quality assessment of MRSI spectra is not only a tedious and time-consuming task, but is also affected by human subjectivity. Consequently, automatic, fast and reliable methods for spectral quality assessment are of utmost interest. In this article, we present a new random forest-based method for automatic quality assessment of (1) H MRSI brain spectra, which uses a new set of MRS signal features. The random forest classifier was trained on spectra from 40 MRSI grids that were classified as acceptable or non-acceptable by two expert spectroscopists. To account for the effects of intra-rater reliability, each spectrum was rated for quality three times by each rater. The automatic method classified these spectra with an area under the curve (AUC) of 0.976. Furthermore, in the subset of spectra containing only the cases that were classified every time in the same way by the spectroscopists, an AUC of 0.998 was obtained. Feature importance for the classification was also evaluated. Frequency domain skewness and kurtosis, as well as time domain signal-to-noise ratios (SNRs) in the ranges 50-75 ms and 75-100 ms, were the most important features. Given that the method is able to assess a whole MRSI grid faster than a spectroscopist (approximately 3 s versus approximately 3 min), and without loss of accuracy (agreement between classifier trained with just one session and any of the other labelling sessions, 89.88%; agreement between any two labelling sessions, 89.03%), the authors suggest its implementation in the clinical routine. The method presented in this article was implemented in jMRUI's SpectrIm plugin. Copyright © 2016 John Wiley & Sons, Ltd.

Definición de los procedimientos e indicadores de la cadena de custodia de la industria de pasta y papel vinculados a la normativa ISO 9000/14000

En el trabajo se ha reflejado la génesis del término „desarrollo sostenible‟ y la preocupación social y de los gobiernos hacia la sostenibilidad de los recursos, generando una política forestal a escala internacional, cuyo hito inicial desempeña la Cumbre de Rio y otros procesos, donde surge el término „sostenibilidad‟ - procesos gubernamentales que ponen su atención en los bosques,entre ellos el Proceso paneuropeo del que emanan los Criterios e indicadores de la gestión forestal sostenible, así como otros foros donde aparece la vinculación entre los productos y la sostenibilidad de los bosques de donde proceden. A partir de esos conceptos aparecen los sistemas de certificación, primero FSC, promovido por las ONG ambientalistas, y en respuesta a ello, el sistema PEFC de los propietarios forestales privados con las industrias forestales. En su introducción, el trabajo recoge como surge y evoluciona esta preocupación y como se sucede y desarrollan los sistemas de certificación en España, orientados tanto a la superficie forestal como a sus productos derivados. Tratando de ser una herramienta técnica, en estos últimos quince años, se han ido planteando metodologías y propuestas técnicas que puedan garantizar el origen sostenible del bosque de donde procede la materia prima. Aunque la persistencia de la masa forestal como término tiene importancia, no considera numerosos aspectos incluidos en el concepto “gestión forestal sostenible”. El trabajo manifiesta qué es y cómo se origina la Gestión Forestal Sostenible y muy ligado con ello, el origen de la certificación como herramienta, explicando cómo se incardina la certificación forestal española con las estructuras internacionales y se construyen nuevas estructuras a escala española y autonómica. Se expone el dominio y alcance técnico de la certificación, sus inicios y un análisis de la diversidad de sistemas y etiquetas existentes -como ha ido evolucionando a escala internacional y nacional, por sistemas, sectores y continentes, con especial atención en España, recopilando lo sucedido relevante para el sector forestal, industrias forestales y sistemas de certificación en los años de estudio de elaboración de la tesis. Se refleja la relevancia que adquiere la certificación forestal y de la cadena de custodia para la industria del papel, tanto por las regulaciones, normativas y legislación que involucran al producto derivado del bosque como por ser herramienta que enlaza el bosque sostenible con el consumidor. La aplicación de todas esas especificaciones técnicas que muestran la sostenibilidad del bosque y al trazabilidad en el proceso productivo comporta una carga administrativa de recopilación de información, de control para el seguimiento asociado con los registros necesarios, y de archivo de documentos, conforme a las exigencias que plantean los sistemas de certificación forestal. Por tanto, es importante definir un método y procedimientos genéricos para los correspondientes sistemas de gestión preexistentes en las empresas del sector de pasta y papel (de calidad/ de medio ambiente/integrados), para implantar un Sistema de Cadena de Custodia genérico (común a FSC y PEFC) en una instalación de celulosa y papel y un sistema de diligencia debida. Para ello, ha sido necesario analizar la línea de producción y establecer los puntos de su diagrama en los que se requiere el control de la trazabilidad, puntos en los que se procede al seguimiento y registro de la materia prima, materia semielaborada y producto, y de ahí proceder a redactar o retocar los procedimientos de gestión calidad/ medioambiental, en su caso, para incluir los campos de registro. Según determinen los procedimientos, se efectuará un seguimiento y registro de los, derivados que configuran una característica y se determinará una serie de indicadores del sistema de trazabilidad de la madera en la industria de celulosa y papel, es decir, un conjunto de parámetros cuantitativos y descriptivos, sujetos al seguimiento de forma periódica, que muestren el cambio y permitan observar la evaluación y control del Sistema de Cadena de Custodia. Además de asegurar la trazabilidad de la madera y fibra en la industria de pasta y papel y con ello la sostenibilidad del bosque del que procede, se avalará la legalidad de los aprovechamientos que proporcionan ese recurso maderable, cumpliendo así no sólo la legislación vigente sino también ambos sistemas de certificación FSC y PEFC. El sistema de cadena de custodia de la pasta y papel se caracteriza por los indicadores de seguimiento que permite el control de la trazabilidad. ABSTRACT This paper traces the origins of the term „Sustainable Development‟ and of both citizen and institutional concern for the sustainability of resources, leading to the enactment of a forestry policy at international level, of which the initial milestones are the Rio Summit and other processes in which the term „Sustainability‟ was born. Those forestfocused institutional initiatives include the pan-European process that led to the publication of Sustainable Forest Management Criteria and Indicators, and other forums that highlight the link between finished wood-based products and the sustainability of the forests from which that wood is sourced. Those concepts were the culture in which forest certification systems were engendered, first FSC, promoted by environmental NGOs, and subsequently PEFC, fostered in response to FSC by private forest owners and forest-based industries. In its Introduction, this paper looks at how such concern arose and has evolved and how certification systems came into existence in Spain and developed to encompass both forest lands and forest-based products. As part of a mission to provide an applicable technical tool, new methodologies and technical proposals have been put forward over the past fifteen years aimed at guaranteeing the sustainable origin of the forest from which raw material is sourced. Although the maintenance of forest stands as a term in its own right is important, it does not take many of the aspects included in the concept of “sustainable forest management” into account. This thesis describes what SFM is and how it was born, underlying the close link between SFM and the origin of certification as a tool, explaining how Spanish forest certification is embodied in international structures, while new structures are built here in Spain on both the national and regional scale. This work also details the domain and scope of forest certification from the technical standpoint, explains its beginnings, and assesses the various systems and labels that exist - how certification has evolved internationally and nationally across systems, sectors and continents, with special emphasis on Spain. It provides a compilation of events relevant to forestry, forest industries and forest certification systems that have taken place during the years this thesis has been in preparation. It reflects on the relevance that forest and chain of custody certification holds for the paper industry, in view not only of the regulations, policies and legislation that affect forest-based products but also of its role as a tool that bonds the sustainable forest with the consumer. Implementing the range of technical specifications to demonstrate forest sustainability and traceability throughout the production process entails the administrative burden of collecting information and providing controls to process the relevant records and documents to be kept on file in compliance with the requirements made by forest certification schemes. It is therefore important to define a generic method, together with its relevant procedures,that fits the management systems (quality / environmental / integrated)existing today in pulp and paper companies, in order to implement a generic Chain of Custody scheme (common to FSC and PEFC) in a pulp and paper mill, and a due diligence system. To achieve that, it has first been necessary to analyse the production line and establish points along the route where traceabilitycontrols need to be implemented and points where raw material, semi-finished goods and end products should be monitored and recorded. Subsequently, the procedures in quality / environmental management systems need to be drafted or amended as required to include fields that reflect those records. As required by the procedures, forest-based products that have a specific characteristic shall be monitored and recorded, and a number of indicators identified in the traceability system of wood for pulp & paper, i.e.createa set of quantitative and descriptive parameters subject to regular monitoringthat reveal changes and enable the Chain of Custody system to be assessed and controlled. In addition to ensuring the traceability of wood and fibre in the pulp and paper industry -and so the sustainability of the forest from which it is sourced -, the legality of the harvesting that produces that timber will also be enhanced, thus fulfilling not only the law but also both FSC and PEFC certification schemes. The chain of custody system for pulp and paper is characterised by monitoring indicators that enable traceability to be controlled.

Den lilla kemifabriken : En studie för att undersöka om nyttan av skogsrester kan ökas i norra Sveriges inland

The background of this work is to suggest ways to take care of branches and tops of trees that today are left out in the north of Sweden after logging because it has to low value to be worth transporting. A solution to this is to place small chemical factories in the sparsely populated areas in the inland of Norrland that can take care of the forest residues and break it into valuable chemicals directly in the forest an then transport it to a market. The aim of this work was to find out if it´s a good idea to invest in these small chemical factories in the north of Sweden. This study has been carried out using literature study and interviews of key people. The largest part of the result comes from the interviews. The results of this study show that the small chemical factory is a good idea. Forest residues contains many valuable substances that should be greater used today. The results section of the report describes various factor that are crucial for the small chemical factory and these are: the products that can be produced, what technology that is suitable, if there is an market, who should be taking care of the factory and how the inland endurance will be affected. The conclusions that can be drawn from the study is that the small chemical factory should produce high-grade-sary chemicals directed at the chemical market. It may also be noted that there is existing technology that can be used in the factories, what has been done in the laboratories today can be implemented in the factory. The market will obviously depend on which product that will be produces, but finding a suitable market should not be impossible. The inland endurance will be positively impacted, among other things, the social endurance is enhances when these small chemical factories creates job opportunities in the inland and it can lead to decreasing the emigration.

Environmental impacts of freshwater use and suspended solids in life cycle assessment

Perturbation of natural ecosystems, namely by increasing freshwater use and its degradative use, as well as topsoil erosion by water of land-use production systems, have been emerging as topics of high environmental concern. Freshwater use has become a focus of attention in the last few years for all stakeholders involved in the production of goods, mainly agro-industrial and forest-based products, which are freshwater-intensive consumers, requiring large inputs of green and blue water. This thesis presents a global review on the available Water Footprint Assessment and Life Cycle Assessment (LCA)-based methods for measuring and assessing the environmental relevance of freshwater resources use, based on a life cycle perspective. Using some of the available midpoint LCA-based methods, the freshwater use-related impacts of a Portuguese wine (white ‘vinho verde’) were assessed. However, the relevance of environmental green water has been neglected because of the absence of a comprehensive impact assessment method associated with green water flows. To overcome this constraint, this thesis helps to improve and enhance the LCA-based methods by providing a midpoint and spatially explicit Life Cycle Impact Assessment (LCIA) method for assessing impacts on terrestrial green water flow and addressing reductions in surface blue water production caused by reductions in surface runoff due to land-use production systems. The applicability of the proposed method is illustrated by a case study on Eucalyptus globulus conducted in Portugal, as the growth of short rotation forestry is largely dependent on local precipitation. Topsoil erosion by water has been characterised as one of the most upsetting problems for rivers. Because of this, this thesis also focuses on the ecosystem impacts caused by suspended solids (SS) from topsoil erosion that reach freshwater systems. A framework to conduct a spatially distributed SS delivery to freshwater streams and a fate and effect LCIA method to derive site-specific characterisation factors (CFs) for endpoint damage on aquatic ecosystem diversity, namely on algae, macrophyte, and macroinvertebrates organisms, were developed. The applicability of this framework, combined with the derived site-specific CFs, is shown by conducting a case study on E. globulus stands located in Portugal as an example of a land use based system. A spatially explicit LCA assessment was shown to be necessary, since the impacts associated with both green water flows and SS vary greatly as a function of spatial location.